Anatomy of a Pen

I’ve written recently about machining my own custom pen because, much like lamps, they are a “form over function” project where the end result can be gorgeous as well as useful. Aesthetically pleasing to everyone, not just techie people. And they don’t take up a lot of space!

Initially, my design for the first pen was sketched out in notebooks, and then modelled in CAD, then back to the notebooks when I was in the shop. This helped me get a general feel for what I wanted, but many style, material, and mechanical considerations had to be redesigned on the fly as I found techniques that didn’t work, and others that did.

A lot of the dimensions of final product came down to how they felt in my hands, as I was building. That’s fine for a one-off, but I’d kinda like to parameterize basic measurements so that I have some guidelines on what works for future pens.

So here’s a pretty generic pen, modeled in Solidworks.

Here are a few pens I had within arm’s reach.

Starting at the top, I named these 1-4, and made some basic measurements based on the generic model:

Now I’ve got a good baseline for what makes a comfortable writing utensil, a recommendation for critical dimensions to stay within, and some language (or at least letters) to be able to intelligently discuss the anatomy of a pen.